import math

#获取数据
def getNum():
    ls = []
    x = input('请输入数字（直接输入回车推出）:')
    while not x =='':
        ls.append(eval(x))
        x = input('请输入数字（直接输入回车推出）:')

    return ls
#计算平均值
def mean(ls):
    n = len(ls)
    avg = sum(ls)/n
    return avg

#计算标准差
def dev(ls):
    n = len(ls)
    avg= sum(ls) / n
    variance = sum((x - avg) ** 2 for x in ls) / n
    dev = math.sqrt(variance)
    return dev


#计算中位数
def median(ls):
    a = sorted(ls)
    n = len(ls)
    if n % 2 == 0:
        median = ( a[n // 2 - 1] +   a[n // 2]) / 2
    else:
        median =   a[n // 2]
    return median
a = getNum()
b = mean(a)
c = dev(a)
d = median(a)

print(b,c,d)



